Power control circuit for vehicle and operating method thereof

Abstract

A power control circuit for a vehicle includes a power switch, N-type semiconductor switches electrically connected between a power supply terminal to which an input voltage is applied and the power switch and in which the N-type semiconductor switches are connected back-to-back, a charge pump circuit for generating a drive voltage to drive the N-type semiconductor switches by boosting the input voltage, a reverse voltage protection circuit electrically connected between an output terminal of the charge pump circuit and a node in which the N-type semiconductor switches are connected to each other, a microcontroller for generating a pulse width modulation signal for the operation of the charge pump circuit, and a voltage attenuation circuit for attenuating the drive voltage and applying the attenuated drive voltage to the microcontroller.

What is claimed is: 
     
       1. A power control circuit for a vehicle, the power control circuit comprising:
 at least one power switch; 
 N-type semiconductor switches electrically connected between a power supply terminal to which an input voltage is applied and the at least one power switch, wherein the N-type semiconductor switches are connected back-to-back; 
 a charge pump circuit configured to generate a drive voltage for driving the N-type semiconductor switches by boosting the input voltage; 
 a microcontroller configured to generate a pulse width modulation (PWM) signal for the operation of the charge pump circuit; and 
 a voltage attenuation circuit configured to attenuate the drive voltage and apply the attenuated drive voltage to the microcontroller. 
 
     
     
       2. The power control circuit of  claim 1 , wherein the charge pump circuit comprises:
 a plurality of diodes connected in series; 
 a plurality of capacitors connected to cathode terminals of the plurality of diodes, respectively; and 
 at least one first semiconductor switch connected between a ground terminal and one terminal of at least one of the plurality of capacitors, respectively, wherein the at least one first semiconductor switch is configured to selectively turned on based on the PWM signal. 
 
     
     
       3. The power control circuit of  claim 1 , further comprising a second semiconductor switch electrically connected between the power supply terminal and the charge pump circuit, wherein:
 the second semiconductor switch is selectively turned on based on a signal from the microcontroller; and 
 the charge pump circuit is supplied with the input voltage based on the second semiconductor switch being turned on. 
 
     
     
       4. The power control circuit of  claim 1 , further comprising:
 a reverse voltage protection circuit electrically connected between an output terminal of the charge pump circuit and a node in which the N-type semiconductor switches are connected to each other. 
 
     
     
       5. The power control circuit of  claim 4 , wherein the reverse voltage protection circuit comprises:
 a first resistor connected between the node and the output terminal; 
 a first diode connected in parallel with the first resistor; 
 a third semiconductor switch having a first terminal connected to the output terminal; 
 a second resistor connected between a second terminal of the third semiconductor switch and the node; 
 a third resistor connected between the second terminal of the third semiconductor and a ground terminal; and 
 a second diode connected between a third terminal of the third semiconductor switch and the node. 
 
     
     
       6. The power control circuit of  claim 5 , wherein the third semiconductor switch is turned on, based a reverse voltage being applied between the power supply terminal and the ground terminal, to form a voltage higher by a threshold voltage of the second diode than a ground voltage at the output terminal of the charge pump circuit. 
     
     
       7. The power control circuit of  claim 1 , wherein the at least one power switch comprises:
 a first power switch configured to selectively supply the input voltage to a load; and 
 a second power switch configured to selectively supply the input power to a heater adjusting temperature of a battery cell. 
 
     
     
       8. The power control circuit of  claim 1 , wherein the microcontroller further configured to:
 measure the drive voltage; and 
 determine whether the charge pump circuit is faulty based on the measured drive voltage. 
 
     
     
       9. The power control circuit of  claim 8 , wherein the microcontroller further configured to:
 measure the input voltage; and 
 determine that the charge pump circuit is faulty based on difference between the measured drive voltage and a value obtained by multiplying the measured input voltage by a boost ratio of the charge pump circuit being equal to or greater than a predetermined first threshold. 
 
     
     
       10. The power control circuit of  claim 8 , wherein the microcontroller stops generating the PWM signal based on the charge pump circuit being determined to be faulty. 
     
     
       11. The power control circuit of  claim 1 , further comprising a cutoff circuit configured to forcibly turn off the N-type semiconductor switches based on a fail-mode flag signal from the microcontroller. 
     
     
       12. The power control circuit of  claim 11 , wherein the cutoff circuit comprises:
 a diode having an anode terminal connected to an output port through which the microcontroller outputs the fail-mode flag signal; and 
 a fourth semiconductor switch having a first terminal connected to the output terminal of the charge pump circuit, a second terminal connected to a ground terminal, and a third terminal connected to the anode terminal of the diode, wherein the fourth semiconductor switch is turned on based on the fail-mode signal having a first logic level. 
 
     
     
       13. The power control circuit of  claim 12 , wherein the microcontroller further configured to output the fail-mode signal having the first logic level based on a short circuit being detected in an internal component of the at least one switch or in a load connected to the at least one power switch. 
     
     
       14. The power control circuit of  claim 1 , further comprising a cutoff circuit configured to forcibly turn off the N-type semiconductor switches based on a collision flag signal indicating occurrence of a collision with the vehicle. 
     
     
       15. The power control circuit of  claim 14 , wherein the cutoff circuit comprises:
 a fifth switch and a sixth switch that are selectively turned on based on the collision flag signal; 
 a diode having an anode terminal connected to one terminal of the sixth semiconductor switch; and 
 a fourth semiconductor switch having a first terminal connected to the output terminal of the charge pump circuit, a second terminal connected to a ground terminal, and a third terminal connected to a cathode terminal of the diode. 
 
     
     
       16. The power control circuit of  claim 15 , wherein:
 the anode terminal of the diode is electrically connected to a control terminal of a latch relay which selectively connects the power supply terminal and a battery cell based on a signal applied to the control terminal; and 
 the cutoff circuit is configured to forcibly turn off the latch relay based on the collision flag signal having a first logic level being applied. 
 
     
     
       17. The power control circuit of  claim 16 , wherein the microcontroller further configured to:
 measure the drive voltage and voltages at both ends of the latch relay; and 
 determine whether the N-type semiconductor switches and the latch relay are turned off based on the measured drive voltage and the measured voltages at both ends of the latch relay. 
 
     
     
       18. The power control circuit of  claim 17 , wherein the microcontroller determines that the N-type semiconductor switches and the latch relay are turned off based on the measured drive voltage being equal to or less than a predetermined second threshold and based on a difference between the measured voltages at both ends of the latch relay being equal to or greater than a predetermined third threshold. 
     
     
       19. A vehicle comprising the power control circuit of  claim 1 . 
     
     
       20. A method of operating a power control circuit including at least one power switch, N-type semiconductor switches electrically connected between a power supply terminal to which an input voltage is applied and the at least one power switch, wherein the N-type semiconductor switches being connected back-to-back, and a charge pump circuit configured to generate a drive voltage for driving the N-type semiconductor switches by boosting the input voltage, the method comprising:
 generating, by a microcontroller, a pulse width modulation (PWM) signal for the operation of the charge pump circuit; 
 measuring, by the microcontroller, the input voltage and the drive voltage; and 
 determining, by the microcontroller, whether the charge pump circuit is faulty based on the measured input voltage and the measured drive voltage satisfying a predetermined first condition.